Preheat your oven to 375°F (190°C).
In a large skillet, melt the butter over medium heat.
Stir in the flour, garlic powder, and onion powder.
Gradually whisk in the chicken broth and allow it to thicken.
Add chicken, mixed vegetables, pepper, and shredded cheese.
Remove the mixture from heat once it's thick and creamy.
In a separate bowl, combine the biscuit mix and milk.
Spoon the filling into a greased baking dish.
Dollop spoonfuls of biscuit dough over the filling, spreading as necessary.
Bake for 25-30 minutes or until the biscuits are golden brown.
Let cool for a few minutes before serving.